The present disclosure relates generally to radio frequency systems and, more particularly, to switching power amplifiers used in a radio frequency system.
This section is intended to introduce the reader to various aspects of art that may be related to various aspects of the present techniques, which are described and/or claimed below. This discussion is believed to be helpful in providing the reader with background information to facilitate a better understanding of the various aspects of the present disclosure. Accordingly, it should be understood that these statements are to be read in this light, and not as admissions of prior art.
Many electronic devices may include a radio frequency system to facilitate wireless communication of data with another electronic device and/or a network. The radio frequency system may include a transceiver that outputs an analog representation of data as an analog electrical signal, which may then be wirelessly transmitted via an antenna. Since the electronic device may be separated by some distance, the radio frequency system may include an amplifier component to control the output power (e.g., strength of analog electrical signals) of the radio frequency system.
In some embodiments, the amplifier component may include a switching (e.g., class-D) power amplifier, which utilizes one or more transistors as electronic switches. In some embodiments, the switching power amplifier may amplify an input analog electrical signal to a desired output power. More specifically, the switching power amplifier may generate the amplified analog electrical signal by connecting an output to an envelope voltage (e.g., Venv) supply rail or ground based at least in part on an input analog electrical signal.
Ideally, the switching power amplifier should achieve high power efficiency (e.g., output power/DC power consumption), linearly adjust the output power of the amplified analog electrical signals, and maintain a constant phase shift between the input analog electrical signals and the output amplified analog electrical signals. However, in real-world operation, a transistor generally has parasitic capacitance, which may cause the transistor to conduct leakage current from its gate to its drain. In fact, this leakage current may affect power efficiency of the switching power amplifier, linearity of adjustments to the output power, and/or consistency of the phase shift between the input and output amplified analog electrical signals.